业务更名为撞车并切换crash路由

用户可见文案与页面/API路径改为撞车与crash，保留mohong表与权限码兼容；移动端入口去掉租/撞图标。

frontend/src/features/mohong/components/MohongCartPanel.vue

@@ -69,7 +69,7 @@ async function handleCheckout() {
     clearCart()
     closeCart()
     const payment = await startMohongPayment(order.id, payWay)
-    const orderPath = props.mobile ? `/m/mohong/orders/${order.id}` : `/mohong/orders/${order.id}`
+    const orderPath = props.mobile ? `/m/crash/orders/${order.id}` : `/crash/orders/${order.id}`
     if (payment.paid || payment.status === 'paid') {
       ElMessage.success('支付成功')
       await router.push(orderPath)

frontend/src/features/mohong/components/MohongProductCard.vue

@@ -18,7 +18,7 @@ const stockLabel = computed(() => {
 </script>
 
 <template>
-  <RouterLink class="mohong-card" :to="`/mohong/${product.id}`">
+  <RouterLink class="mohong-card" :to="`/crash/${product.id}`">
     <div class="card-cover">
       <img
         v-if="showImage"